This invention relates to an .omega.-hydroxy-(.omega.-3)-ketonitrile which is important as a synthetic intermediate or starting material for preparing various compounds, particularly important for preparing an .omega.-hydroxy fatty acid which is an important intermediate of macrocyclic lactone type perfumes, and a method for producing an .omega.-hydroxy fatty acid using the same.
There have been known many methods for producing an .omega.-hydroxy fatty acid which is an important intermediate of macrocyclic lactone type perfumes. Typical examples thereof are introduced in "Perfume Chemical Comprehensive 2", by Osamu Okuda, Hirokawa Shoten, p. 1211 and "Perfume Chemical Comprehensive 3", by Osamu Okuda, Hirokawa Shoten, p.p. 172-174 and 176-177.
The above methods include several drawbacks that these have many steps and are troublesome in handling, expensive agents or agents accompanied by dangers in handling are often required, and also the yield is poor.
The present inventors have studied about a method for preparing .omega.-hydroxy fatty acid which can solve the problems of the prior art as mentioned above and proposed in Japanese Provisional Patent Publications No. 11036/1991 and No. 11046/1991 (which corresponds to U.S. Pat. Nos. 5,023,351 and 5,099,036 or EP-A-402 063) that an .alpha.-(.omega.-cyanoalkanoyl)-.gamma.-butyrolactone (II) is reacted in an aqueous solution in the presence of 2 to 20 mole of an alkali metal hydroxide per mole of said butyrolactone to obtain an .omega.-hydroxy-(.omega.-3)-keto fatty acid (III) and then the acid is reacted with hydrazine to prepare an .omega.-hydroxy fatty acid (IV). However, in this method, it is difficult to separate the intermediate (III) since it is water-soluble. ##STR2## wherein n is an integer of 7 to 11.